Maybe he'd like to get to know you better, but he's shy and unsure what to say in an actual message. Or, he might be the kind of guy who winks at a lot of woman and can't be bothered sending a message. If this is the case, it doesn't mean much.
The law of conservation of mass (from Lavoisier) states that mass can be neither created nor destroyed (but it may change its form into something that is not desired, such as heat with an engine) or that in a chemical reaction, the total mass of the reacting substances is equal to the total mass of products formed.
The materials to the right of the arrow are the products, or materials that have been produced by the reaction. The Law of Conservation of Mass states that in a chemical reaction no mass is lost or gained. The Law of Conservation of Mass applies to individual types of atom. One could say that for any element, there is no loss or gain of that element in a chemical reaction. There are such things as reversible reactions, reactions in which the products reassemble to become the original products.